Fumigation investigations in California . dustry, see Bulletin 123,Bureau of Plant Industry, United States Department of Agriculture1, which may beobtained for 20 cents from the Superintendent of Government PrintingOffice, Washington. D. C. l.\>i ( I in BMIES OF CI nils i RUITS. 11 generally so destructive as to require extended efforts for theircontrol are the purple scale (Lepidosaphes beckii Newm.), the redscale ( ChrysompTialus aurantii Mask.), and the Mack Bcale {Saisseiiaolese Bern.). The yellow scale {Chry8(ymphalus citrinus Coq.), con-sidered a variety of the red scale,
Fumigation investigations in California . dustry, see Bulletin 123,Bureau of Plant Industry, United States Department of Agriculture1, which may beobtained for 20 cents from the Superintendent of Government PrintingOffice, Washington. D. C. l.\>i ( I in BMIES OF CI nils i RUITS. 11 generally so destructive as to require extended efforts for theircontrol are the purple scale (Lepidosaphes beckii Newm.), the redscale ( ChrysompTialus aurantii Mask.), and the Mack Bcale {Saisseiiaolese Bern.). The yellow scale {Chry8(ymphalus citrinus Coq.), con-sidered a variety of the red scale, is much Less destructive generally,though sufficiently troublesome in some Localities to be considered apest of primary importance. Other scale-insects attacking citrustrees, which are so perfectly held in control by their natural enemiesand other causes as seldom to become very destructive, are the softbrown scale (Coccus Kesperidum \..\ the hemispherical scale ( Targ.), the oleander scale {Aspidiotus hederse Val.),. Fig. 2.—Leaves and branch of orange infested with purple scale (Lcpidosaphes beckii). (Original.) and the cottony cushion scale (Icerya purchasi Mask.). Mealy bugs(Pseudococcus spp.) are quite generally prevalent. The most important pests other than scale-insects are to be foundamong the mites, of which the rust mite of the orange or silver miteof the lemon (Phyllocoptes oleivorus Ashm.) and the citrus red spider{Tetranychus mytilaspidis Riley) an4 highly injurious. The orangeaphis (Aphis gossypii Glov.) becomes very numerous during someseasons but is soon attacked by its natural enemies and held in con-trol. A species of thrips worked quite extensively in some localitieson ripe oranges during the first months of 1908, removing the coloringmatter from beneath the epidermis, thus giving to the fruit a spottedappearance which lowered its market grade. The purple scale (figs. 2 and 3) appears to prefer the more moisldons in the vicinitv of the
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectfumigation, bookyear1
